1. Field of the Invention
The present invention is related to an image forming apparatus such as a copier or a printer, and more particularly, to a paper guide for guiding a printing paper entering a fusing unit of an electrophotographic image forming apparatus.
2. Description of the Related Art
In general, the method of printing an image on a printing paper in an electrophotographic image forming apparatus comprises transcribing a predetermined image, which is developed by a toner on a printing paper, fusing the transcribed image onto the printing paper by heating and pressing, and then discharging the printing paper through a paper discharging unit. The image forming apparatus comprises a paper guide between a developing unit and a fusing unit, for guiding the printing paper from the developing unit to the fusing unit. The paper guide 10 comprises a plurality of guiding ribs 13 on a guiding member 11, as shown in FIG. 1 to avoid staining an unprinted face of a printing paper in one side printing or a preprinted face in double side printing by the paper guide 10.
Further, in order to prevent the printing paper passed through the fusing unit from creasing, the center of the paper guide may be formed higher than both of the edge side (Japanese Patent No. 2002-337403).
However, the paper guide 10 causes a plurality of stripes 22 on an image which is fused on the printing paper 20 after the paper 20 has passed through the fusing unit along the paper guide 10, as shown in FIG. 2. The stripes 22 occur at positions corresponding to positions of a plurality of guiding ribs 13 formed in the paper guide 10 due to a temperature difference between the guiding ribs 13 and spaces 15 between the guiding ribs 13. That is, different degrees of heat are transferred onto the printing paper 20 from the paper guide 10 depending on whether the printing paper 20 contacts the guiding ribs 13 or the spaces 15. Accordingly, a density difference occurs on the image fused by the fusing unit, causing a plurality of stripes 22 on the printed image 21.
Accordingly, in order to overcome the above and/or other problems, a paper guide of an electrophotographic image forming apparatus, which does not stain a printing paper with stripes after fusing is needed.